Backflow Prevention

Backflow assembly tests in Oxnard can only be conducted by businesses that are certified by the County of Ventura Environmental Health Department and are licensed to do business within the City of Oxnard. See below for a list of testers.

A cross connection is any connection between piping that carries drinking water (or potable water) and the piping or fixtures that carry water not suitable for drinking (or non-potable water) or other substances that are not safe to drink, such as cleaning products, yard and garden chemicals, automotive products, water from irrigation systems, fire sprinkler systems, or private wells.

The Federal Safe Drinking Water Act sets the overall public health standards for public drinking water systems. The federal government has delegated authority for overseeing drinking water standards in the state to the California Department of Health Services. Title 17 of the California Code of Regulations requires every water purveyor to administer a cross connection control program that protects the potable water supply from potential sources of contamination.

Drinking water normally flows in one direction, from the water meter to a plumbing fixture. Under certain circumstances, it can flow in the opposite direction — this is called “backflow”. A backflow incident can happen at any time. All that is needed is a water pressure drop in the public water system main line, most commonly caused by firefighting, hydrant flushing, flow testing, a water main break, or extreme high usage on the water system.

If such a pressure drop occurs, any connection to a non-potable water source could be siphoned back into the customer’s drinking water piping, polluting the water within the home, and even into the water mains in the street, polluting the public water system. The only way to prevent such incidents from occurring and to maintain safe drinking water is to use backflow prevention devices and to make sure that they are correctly installed and adequately maintained. Our drinking water is among the safest in the world, but it requires efforts from all of us to keep it that way.

Backflow assemblies are devices placed on cross connections to prevent water from backflowing into the public water system. The most common type of backflow assembly is a double check valve assembly, which consist of two independent check valves, two resilient seated shut off valves and test cocks. To ensure they work correctly, all backflow assemblies must be tested annually with the exception of atmospheric vacuum breakers.

If your irrigation system, fire sprinkler system, swimming pool, or spa was permitted with a building permit through the City Development Services Department when it was installed, adequate backflow protection was required. If you are not sure if it was permitted or if you are not sure if backflow protection was properly installed, please contact the Public Works Department Call Center, at (805) 385-8136. We will be glad to perform a survey for you.

The water supplier is responsible for water quality and for implementing and maintaining a cross connection control program to prevent pollution or contamination of the public water system. The water supplier’s responsibility ends at the outlet side (the customer’s side) of the water meter. Once the water is on the outlet side of the water meter or service connection, responsibility and liability falls to the owner or property manager.